This one has me stumped: I have a spreadsheet that I need to know when I have a cell that is greater than another cell but show nothing when it doesn't.

Cell B9 is a sum of B2:B8 with these cells using information from other sheets in the workbook. Cell B13 is a number that I input. I am trying to get the sum of B9-B13 only when it is greater than B13, I need this cell to be blank when the sum is equal to or less than B13.

I know I am missing something simple but I cannot get the cell blank when it needs be. I am using Excel 2010, but it will also need to work in 2007 version.

Thanks!